The invention relates to an exhaust gas turbocharger for an internal combustion engine including an exhaust gas turbine with a guide vane structure disposed in the turbine inlet passage for controlling the flow of exhaust gas into the turbine.
The laid-open specification DE 10 2005 027 080 A1 discloses an exhaust gas turbocharger for an internal combustion engine, whose exhaust gas carrying section has a guide device for controlling the admission of exhaust gas to the turbine wheel of the exhaust gas turbocharger, wherein the guide device comprises an annular guide vane ring for directing the exhaust gas flow into the turbocharger, the flow volume being controlled by an axial slide. The annular guide vane ring is firmly mounted in the exhaust gas inlet passage and is fixed concentrically to an axis of rotation of the turbine wheel.
For changing the charging of the turbine wheel by the exhaust gas, the axial slide which is arranged coaxially to the turbine wheel and the annular guide vane structure can be displaced in a translatory manner, wherein the axial slide has a matrix in the form of an annular recess at the end facing the annular guide vane structure, which recess is designed to accommodate the annular guide vane structure at its end facing the axial slide. For the reliable function of the exhaust gas turbocharger, it is thereby necessary to provide a contact gap between the matrix and the annular guide vane structure, so that a canting can be avoided during the displacement of the axial slide. For securing the movement gap accompanying the movement freedom between the matrix and the annular guide vane structure, an elaborate design of the exhaust gas turbocharger is provided resulting from the fixing or mounting of the annular guide vane structure.
The annular guide vane structure includes a support which no exhaust gas can flow and a guide vane structure through which exhaust gas is conducted and which is fastened to the support. The support serves for mounting the annular guide vane structure on the one hand, and, on the other hand, it serves for the fastening of the annular guide vanes. The support essentially represents the more stable part of the annular guide vane structure. If, as shown in the state of the art, the axial slide is guided over the annular guide vane structure receiving the guide vanes starting from an end of the guide vanes arranged facing away from the support, the danger exists essentially that even a minimal inclination of the guide vanes causes a canting between the annular guide vane structure and the axial slide. The canting possibly results in an unsafe operation or a total failure of the exhaust gas turbocharger.
It is the object of the present invention to provide an assembly-friendly and operation-safe exhaust gas turbo-charger.